Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose har...Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose hardness is 65 HRC and flexural strength is 1450 MPa.The high-temperature oxidation mechanism of TiC-based cermets was investigated through an X-ray diffractometer and scanning electron microscope.The added elements Ni and Cr along with their solid solutions not only bond with the hard phase TiC to ensure the physical performance of the cermet,but also impede the internal diffusion during oxidation by forming a dense composite oxide layer,thereby enhancing the oxidation resistance.The TiC-NiCr cermet exhibits a dense protective oxide layer at 900℃ and can endure continuous oxidation for approximately 1000 h.A methodology for fabricating TiC-NiCr metal matrix composites is proposed,and their oxidation resistance is evaluated,providing a theoretical and practical basis for simultaneously enhancing the mechanical properties and oxidation resistance and reducing production costs.展开更多
In-situ formed TiC particles were introduced into α-Fe matrix as corrosion-resistant phases to enhance corrosion resistance against aluminum melt of the alloy.The effects of TiC content on the microstructure and corr...In-situ formed TiC particles were introduced into α-Fe matrix as corrosion-resistant phases to enhance corrosion resistance against aluminum melt of the alloy.The effects of TiC content on the microstructure and corrosion behavior of Fe-TiC alloys were examined both experimentally and theoretically.The results indicate that eutectic Fe-6TiC alloy offers superior corrosion resistance to liquid aluminum,which is 7.5 times greater than that of H13 die steel.The long rod-shaped and granular eutectic TiC particles provide superior resistance to aluminum melt diffusion compared to blocky primary TiC.Moreover,these eutectic TiC particles improve the bonding strength of the intermetallic compound layer,inhibiting cracking,peeling,and dissolution of the corrosion layer.A novel theoretical numerical model is established to quantitatively account for the corrosion behavior of the ferrous alloys in aluminum melt,and the diffusion inhibition factor λ and dissolution inhibition factorεare introduced in this work to quantitatively estimate the corrosion performance.Theoretical analysis demonstrates that Fe-6TiC eutectic alloy containing numerous long rod-shaped and granular eutectic TiC exhibits the best corrosion resistance.展开更多
基金National Natural Science Foundation of China(52376076)Open Fund of Material Corrosion and Protection Key Laboratory of Sichuan Province(2023CL13)Laiwu Vocational and Technical College Teachers Research Fund(2023jsky05)。
文摘Powder metallurgy was used to fabricate TiC-NiCr cermets and the oxidation behavior at 900℃ was investigated.Results reveal that TiC-NiCr cermets have uniform structures with excellent mechanical properties,whose hardness is 65 HRC and flexural strength is 1450 MPa.The high-temperature oxidation mechanism of TiC-based cermets was investigated through an X-ray diffractometer and scanning electron microscope.The added elements Ni and Cr along with their solid solutions not only bond with the hard phase TiC to ensure the physical performance of the cermet,but also impede the internal diffusion during oxidation by forming a dense composite oxide layer,thereby enhancing the oxidation resistance.The TiC-NiCr cermet exhibits a dense protective oxide layer at 900℃ and can endure continuous oxidation for approximately 1000 h.A methodology for fabricating TiC-NiCr metal matrix composites is proposed,and their oxidation resistance is evaluated,providing a theoretical and practical basis for simultaneously enhancing the mechanical properties and oxidation resistance and reducing production costs.
基金sponsored by the National Natural Science Foundation of China(NSFC)(No.52301097)Shanghai Sailing Program(No.23YF1428800)+1 种基金the National Key Research and Development Program of China(Nos.2021YFB3501001 and 2022YFC2905204)Natural Science Foundation of Shenyang(No.23-503-6-05).
文摘In-situ formed TiC particles were introduced into α-Fe matrix as corrosion-resistant phases to enhance corrosion resistance against aluminum melt of the alloy.The effects of TiC content on the microstructure and corrosion behavior of Fe-TiC alloys were examined both experimentally and theoretically.The results indicate that eutectic Fe-6TiC alloy offers superior corrosion resistance to liquid aluminum,which is 7.5 times greater than that of H13 die steel.The long rod-shaped and granular eutectic TiC particles provide superior resistance to aluminum melt diffusion compared to blocky primary TiC.Moreover,these eutectic TiC particles improve the bonding strength of the intermetallic compound layer,inhibiting cracking,peeling,and dissolution of the corrosion layer.A novel theoretical numerical model is established to quantitatively account for the corrosion behavior of the ferrous alloys in aluminum melt,and the diffusion inhibition factor λ and dissolution inhibition factorεare introduced in this work to quantitatively estimate the corrosion performance.Theoretical analysis demonstrates that Fe-6TiC eutectic alloy containing numerous long rod-shaped and granular eutectic TiC exhibits the best corrosion resistance.
